PURPOSE: To purify a nonprotein nitrogen component contained in cow milk, having low lactose content and useful as a functional food, etc., in high efficiency by desalting a raw material containing nonprotein nitrogen component, treating with an ion exchange resin to effect the adsorption of the component to the resin and desorbing the adsorbed component.
CONSTITUTION: A raw material containing nonprotein nitrogen (NPN) such as cow milk is optionally subjected to ultrafiltration treatment and used as an NPN mother liquor when the NPN-containing raw material is already desalted e.g. by ion exchange treatment or, otherwise, used as the mother liquor after desalting. The obtained NPN mother liquor is subjected to ion-exchange resin treatment comprising a combination of a cation-exchange resin treatment and an anion-exchange resin treatment to make the NPN adsorbed on the resin and the adsorbed component is desorbed from the resin to complete the purification of the nonprotein nitrogen component.
KAKIMOTO KENICHI
TAKANO KOJI
KUWATA TAMOTSU
YAMAMOTO YOSHIRO
